Is it right to make a woman feel unclean?

I was saying 'thank you' to a male colleague and touched his upper arm as a reinforcement of that thanks. He recoiled in disgust, his body language, his facial expression and his yelp surprised me so much that I apologised profusely. The incident happened in front of many children, as I am a teacher at a school. And within a minute he had shook hands with a male colleague. Whether it was his intention or not, I felt that he felt I was unclean. I was/am greatly upset by this. I understand that his cultural or religious beliefs does not permit him to touch women, or vice versa. However, I have lived in many different countries and cultures, and I adhered to their cultural rules and would never have reacted in such an offensive way. What do you think?